Since it resets when you plug in. To prevent false alarms from brief “puffs” of gas the detector has a recheck cycle before alarming. Cut lead wires, faulty circuit connection, a blown or missing fuse, improper supply.
This detector will only indicate the presence of. Propane gas detectors this unit will not work without power. Periodically test the detector's functionality by introducing a controlled amount of propane gas near the.
I would check the power going to it and make sure that everything is connected properly. My best guess would be that your alternating red/green flashing light/beep is a unit malfunction alarm that is being triggered by low voltage. Propane detectors are designed to monitor gas levels. Below is a link to the manual.
Examples causing no power are: Wired directly into the electrical system, the sensor. Below is also a picture of what the beeps mean. Examples causing no power are: